Takayasu arteritis

The main arteries that come out of it, such as the subclavian and carotid arteries. It can also affect other large arteries. It is named after the Japanese physician Mikito Takayasu, who described it in 1907.

Why is it produced?

Within the defense mechanisms we have some types of lymphocytes, B lymphocytes, which transform into plasma cells, the cells responsible for generating antibodies, compounds that detect parts of agents external to the body - antigens - in order to identify possible threats and attack them, as they do with bacteria and viruses.

Under normal conditions, plasma cells only recognize foreign elements as foreign to the body and have mechanisms to also recognize cells and proteins of the body. Now, when for various reasons there is an alteration in this ability to recognize organic components as their own, plasma cells can generate antibodies against the body itself and cause various alterations depending on the type of tissue, cell or protein that they attack. When this happens, it is called an autoimmune disease.

blood vessels are not immune to these possible alterations and when the body creates antibodies that attack these structures, both arterial and venous in their different sizes, vasculitis occurs. In those there is an inflammation of the muscle wall together with a necrosis or death of cells, which compromises the blood supply.

How does Takayasu arteritis occur?

This vasculitis, also called pulseless disease, manifests itself more frequently in Asian women, with a predominance of nine women for each affected male. In the West, fewer than three new cases are detected per year for every million inhabitants.

This disease, of autoimmune origin, is gradually establishing itself. A slow inflammation of the different layers of the aorta occurs, giving a specific inflammatory reaction called granulomatous, which over time causes the arterial walls to become more fibrous, more rigid, and a closure of the lumen of the aorta or supra-aortic vessels, a stenosis. Initially, new small vessels are created that attempt to bypass the obstruction to ensure the blood supply in this way, but little by little this becomes insufficient and symptoms secondary to the stenosis of these great arteries occur.

Depending on the affectation, four types of Takayasu arteritis are differentiated:

• Type I, with involvement of the aorta and supra-aortic trunks
• Type II, with involvement of the abdominal aorta and its branches
• Type III, the sum of type I and type II arteritis
• Type IV, involving the pulmonary artery

Symptoms of vasculitis

The clinical picture of Takayasu's arteritis consists of two phases. In the first stage, there are general symptoms, such as weight loss, lack of appetite and fatigue - what is called a constitutional syndrome - as well as joint and muscle pain (arthromyalgia) and occasionally a not very high fever.

In a second phase, the symptoms due to the occlusion of the arteries occur, with the absence of pulses in different parts of the upper or lower extremities and the presence of murmurs in the arteries, a phenomenon that occurs when the bloodstream has to pass for a smaller glass.

Depending on the artery that is affected, different symptoms will appear. In subclavian artery involvement, a claudication of the upper extremities will be appreciated, that is, pain in the muscle groups of the arms and forearms that prevent their mobilization and that subsides with rest, as well as the phenomenon of, which consists of the appearance of lividity and coldness at the ends of the fingers that then reactively turn red and hot; cold is the main trigger of this phenomenon that occurs in other autoimmune diseases such as systemic.

If the carotid or vertebral arteries, which supply the brain, are affected, symptoms of dizziness, blurred vision, headaches will appear and in cases of severe occlusions, transient ischemic attacks or even may occur.

In the event of significant stenosis of the root of the aorta, the initial part of the aorta that exits the left ventricle, aortic regurgitation and consequently congestive regurgitation can occur.

Occlusion by Takayasu's arteritis of the abdominal aorta and the consequent defect in the intestinal blood supply can cause nausea, vomiting, severe abdominal pain, and intestinal infarcts with necrosis of regions of the intestine.

If the renal arteries are affected, this can lead in the long term to renal failure as well as renal failure.

In the event of coronary involvement, which is rare, episodes of, with, or may occur.

Diagnosis

The diagnosis of Takayasu's arteritis will be based on the symptoms that the patient presents and on the complementary tests that are carried out. On examination, the presence of pulses in the upper and lower extremities should be well evaluated, ensuring that their presence is symmetrical and of equal intensity. Likewise, it is important to auscultate the patient well, looking for heart murmurs and assess the blood pressure in both arms, confirming that the figures are similar.

In the, nonspecific signs can be seen, such as an increase in acute phase reactants, such as CRP and ESR, indicators of an active inflammatory process, as well as a slight increase in white blood cells (leukocytosis) and anemia without alterations in the size of the red blood cells or the hemoglobin in them. There are no specific antibodies for this type of vasculitis.

The study of the arteries will allow to see the different degrees of occlusion, being able to carry out an angiography of the area that is suspected to be affected, although it is preferred to carry out a study of the arteries using non-invasive imaging techniques, such as computerized axial tomography () , which is called CT angiography, or an angio-resonance angiography.

There are a series of six diagnostic criteria for Takayasu arteritis and the presence of three of them is sufficient to establish the existence of this large vessel vasculitis. These criteria are:

• Age less than 40 years.
• Reduction or cancellation of the brachial arterial pulse.
• Claudication of the extremities.
• Difference in blood pressure between the arms greater than 10 mm Hg.
• Presence of murmurs in supra-aortic trunks or abdominal aorta.
• Suggestive angiographic alterations.

Treatment

The treatment of Takayasu arteritis will be based on the use of corticosteroids, which can be associated with immunosuppressants such as methotrexate or azathioprine, as well as modulators of the immune system such as etanercept, infliximab or adalimumab. Treatment with corticosteroids is usually given during outbreaks and with immunosuppressants or immunomodulators between them.

Low-dose aspirin is common to prevent platelet aggregation and thrombus formation.

In cases of severe occlusions, techniques can be performed to unclog the affected arteries through percutaneous transluminal angioplasties, or even perform surgical bypass to bypass the damaged areas in case the occlusions reoccur.

Despite being a disease with a low mortality rate of around 10%, the morbidity, that is, the symptoms it produces and the degree of disability they generate, is high.

Precautionary measures

Takayasu's arteritis, like the rest of vasculitis, is a disease of autoimmune origin, so there are no preventive measures to avoid it. If you suspect it, it is essential to put yourself in the hands of a rheumatologist as soon as possible.

• It is a type of vasculitis. Being a disease of origin autoimmune, there are no preventive measures to avoid it.
• In the first stage there are general symptoms, such as weight loss, lack of appetite and fatigue, joint and muscle pain (arthromyalgia) and sometimes some fever.
• In a second phase, the symptoms occur due to the occlusion of the arteries, with absence of pulses in parts of the upper or lower extremities and murmurs in the arteries